Abstract
Background: Breast cancer survival advancement can be ascribed to various efforts including community screening programs and educational outreach resulting in earlier diagnosis, treatment advances, and more accessible care. However, racial disparities continue to persist. Identification of populations susceptible to adverse health outcomes is substantial to construct health disparities resolutions. The purpose of the study is to identify trends in breast cancer disease specific survival (DSS) in black patients compared to white patients by age at diagnosis, year of diagnosis, and tumor estrogen receptor (ER) status. Methods: The Surveillance, Epidemiology, and End Results database was utilized to identify patients of black or white race diagnosed with stage I-III, ER positive (+) or ER negative (-) breast cancer between 1990 and 2009. The Kaplan-Meier method was used to determine 14-year breast cancer DSS. Changes in DSS were analyzed over the study’s time period and in 3 age groups to evaluate women who were of pre-menopausal age (< 50 years), perimenopausal or postmenopausal and of the average age for breast cancer diagnosis (50-64 years), and elderly (65 + years). Results: The total study sample was 344,142 patients; 309,415 identified as white (89.9%) and 34,727 identified as black (10.1%) women. All patients diagnosed most recently had stable or improving DSS (p<0.05). White patients with ER+ or ER- disease had significantly higher DSS compared to blacks in all age groups and years of diagnosis (p<0.05); more specifically all black patients diagnosed in 2005-2009, had significantly lower disease specific survival (DSS) compared to white patients diagnosed a decade earlier in 1995-1999 (p<0.05). For women 65+ with ER+ cancer, black patients diagnosed between 2005-2009 had a DSS of 86% compared to 91% in white patients diagnosed between 1995-2000. In ER- patients less than 50 years of age, black patients diagnosed between 2005-2009 had 78% DSS compared to white patient DSS of 84% within the same period. Among black patients, young women <50 years of age ER+ and ER- women aged 50-64 years had consistent and most improvement in DSS over the study’s 4 time intervals; for ER+ cancer, DSS was 68% for those diagnosed in 1990-1994, 71% for 1995-1999, 75% for 2000-2005, and 79% for 2006-2009 and for ER- cancer, the DSS was 60% for those diagnosed in 1990-1994, 67% for 1995-1999, and 72% for 2000-2005, and 75% for 2006-2009 (p<0.05). Conclusion: Improvements in breast cancer DSS are evidenced in black and white women, most especially black patients < 50 years of age with ER+ and 50-64 with ER- disease. However, findings demonstrate DSS remain lower in all black patients compared to white patients, independent of year of diagnosis, age, and tumor receptor status. Continued efforts are crucial to identify and address the causes of continued disparities in breast cancer DSS, particularly in subsets of black patients not having survival improvements.
Citation Format: Ewune Ewane, M Yi, A Akhtar, A M Brewster, Lorna McNeil-Haughton, Kelly K Hunt, Dalliah M Black. Differences in breast cancer survival by race, age, and tumor estrogen receptor status [abstract]. In: Proceedings of the Twelfth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2019 Sep 20-23; San Francisco, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl_2):Abstract nr D056.
